If possible you can buy sodahead, it was a lot bigger than blurtit and it has potential to attract a lot of users again and to grow as a top site again. It was one of the top site in US and was growing at rapid speed and it wasn't shut down for low activity. The reason they said was, the income is not enough to maintain the servers. But there are some ways to reduce the server space. I'm not sure, they are ready to sell the source code of the website or not.
I send them few Emails but they didn't reply.